A tennis player lost a match when he yelled at himself on match point and got penalized

Australian-born British tennis player Brydan Klein lost a match on the Challenger Tour in Nottingham, England on Thursday when he was assessed a penalty for unsportsmanlike conduct on match point for yelling "stupid person," via Deadspin.

What makes this especially mind-blowing is that Klein appeared to be yelling at himself.

According to Deadspin, the confusion may have stemmed from an earlier penalty when Klein was complaining about the call from a lineswoman. When Klein later started yelling on match point, the umpire may have thought Klein was yelling about the lineswoman again.